1. Field of the Invention
The present invention relates to an accessory mounting structure for an internal combustion engine, and more particularly to a structure for mounting an accessory or an auxiliary machine for an internal combustion engine.
2. Description of the Related Art
Various structures for supporting accessories on the body of an engine are proposed to mount the accessories to the engine body through a mounting bracket or the like (see, for example, JP 3,342,398B).
JP 3,342,398B discloses an accessory mounting structure for mounting accessories by means of an accessory mounting bracket, in which the accessories such as an alternator (AC generator), a compressor and so on are supported on the accessory mounting bracket (accessory unit block) attached to a side of an internal combustion engine.
The accessory mounting bracket is formed with a water pump housing which constitutes a water pump as an engine accessory, and a cooling water discharge passage extends upward from the water pump housing for cooling water discharged from the water pump. An alternator is mounted on a side of a portion of the accessory mounting bracket in which the cooling water discharge passage is formed.
The cooling water discharge as sage extending upward from the water pump housing is of a broad width, while the accessory mounting bracket portion forming the cooling water discharge passage therein also has a broad width which is substantially equal to the diameter of the concave interior space of the water pump housing. Therefore, the alternator which is attached to the side of the accessory mounting bracket portion is positioned apart from the engine body through the broad-width accessory mounting bracket portion interposed between the engine body and the alternator. Consequently, the alternator is largely separated from the engine body and protrudes sidewise of the water pump, so that the volumetric space occupied by the entire engine assembly is made large.
Further, the alternator having a cylindrical housing is attached to the substantially planar side surface of the accessory mounting bracket portion which extends upward with substantially the same width as the water pump housing. Therefore, the alternator is naturally protruded sidewise of the engine body, and it is difficult to secure a sufficient strength for mounting the alternator to the accessory mounting bracket.
Since most of the engine accessories including the alternator are rotary machines and have cylindrical housings, engine accessories other than the alternator also tend to protrude sidewise to a large extent from the engine body.
The present invention is made in view of the foregoing and the object of the present invention is to provide an accessory mounting structure for an internal combustion engine in which any engine accessories do not protrude to a large extent from the engine body and in which the engine accessories are arranged along the engine body in a compact manner to provide a small-sized engine assembly.